Electronic apparatus transmitting and receiving signal through single wire

ABSTRACT

There is provided an electronic apparatus transmitting and receiving a signal through a single wire that that has a main electronic apparatus and a sub-electronic apparatus connected through a single wire, transmits status information and performs control and communication through the single wire. The electronic apparatus transmitting and receiving a signal through a single wire may include: a sub-electronic apparatus transmitting a detection signal containing status information through a single wire, and performing a predetermined operation upon receiving a response signal to the detection signal; and a main electronic apparatus receiving the detection signal through the single wire and transmitting the response signal having a different signal format from the detection signal to the sub-electronic apparatus.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of Korean Patent Application No.10-2009-0049380 filed on Jun. 4, 2009, in the Korean IntellectualProperty Office, the disclosure of which is incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electronic apparatus transmittingand receiving a signal through a single wire, and more particularly, toan electronic apparatus transmitting and receiving a signal through asingle wire that includes a main electronic apparatus and asub-electronic apparatus connected through a single wire, transmitsstatus information and performs control and communication through thesingle wire.

2. Description of the Related Art

In general, an electronic apparatus may be configured into one setperforming various kinds of operations. Alternatively, an electronicapparatus may include a main electronic apparatus that controls the mainand auxiliary operations and a sub-electronic apparatus that isconnected to the main electronic apparatus and performs the auxiliaryoperation.

The main electronic apparatus and the sub-electronic apparatus may beconnected to each other using a plurality of cables for interfacingoperations such as communications, control and recognition.

However, the plurality of cables, which are physically connected betweenthe main electronic apparatus and the sub-electronic apparatus, increasephysical contact lines to cause difficulties in mechanical design andthus increase manufacturing costs. Besides, when only a small amount ofthe plurality of cables make contact, it becomes impossible to implementa desired operation. Even when an electronic apparatus performsnormally, the electronic apparatus may be determined as a failure due toa simple loose contact.

SUMMARY OF THE INVENTION

An aspect of the present invention provides an electronic apparatustransmitting and receiving a signal through a single wire that has amain electronic apparatus and a sub-electronic apparatus connectedthrough a single wire, transmits status information, and performscontrol and communication through the single wire.

According to an aspect of the present invention, there is provided anelectronic apparatus transmitting and receiving a signal through asingle wire, the electronic apparatus including: a sub-electronicapparatus transmitting a detection signal containing status informationthrough a single wire, and performing a predetermined operation uponreceiving a response signal to the detection signal; and a mainelectronic apparatus receiving the detection signal through the singlewire and transmitting the response signal having a different signalformat from the detection signal to the sub-electronic apparatus.

The main electronic apparatus may include: a control unit transmittingthe response signal according to the status information upon receivingthe detection signal; and a switching unit switching a transmission paththerein according to the reception of the detection signal and thetransmission of the response signal.

The sub-electronic apparatus may include: a detection unit detectinginternal status of the sub-electronic apparatus; and an operation unitperforming a predetermined operation according to the response signal.

The switching unit may include: a first switch being opened when thedetection signal is received and being closed when the response signalis transmitted to form a transmission path for the response signal; adetection resistor supplied with a predetermined operating power andelectrically connected with the detection unit of the sub-electronicapparatus to detect internal status of the sub-electronic apparatus; anda second switch being closed before the detection signal is received toelectrically connect the detection resistor and the detection unit, andbeing opened when the response signal is transmitted.

The switching unit further may include: a pull-up resistor connected inparallel with the detection resistor, receiving the operating power andtransmitting the operating power to the operation unit; and a thirdswitch forming a transmission path for the operating power beingtransmitted to the operation unit from the pull-up resistor.

The control unit may transmit a Pulse Width Modulation (PWM) controlsignal in order to control the operation unit according to the detectionsignal.

The control unit may transmit a start signal according to time divisionto indicate transmission of a signal, the operation unit may transmit anacknowledgement signal according to time division to indicateacknowledgement of reception of the start signal, and a communicationsignal containing data information according to time division may betransmitted and received between the operation unit and the controlunit.

A data format of a signal being transmitted and received between thesub-electronic apparatus and the main electronic apparatus through thesingle wire may include: analog containing status information of thedetection signal; start and address indicating transmission of thesignal from the main electronic apparatus and indicating a data type ofthe signal; data containing data of the signal; and end indicatingtermination of the transmission of the signal.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and other advantages of thepresent invention will be more clearly understood from the followingdetailed description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a view illustrating the configuration of an electronicapparatus according to an exemplary embodiment of the present invention;

FIG. 2 is a view illustrating the structures of signals beingtransmitted and received through a single wire used in an electronicapparatus according to an exemplary embodiment of the present invention;

FIG. 3 is a view illustrating structures of signals being transmittedand received through a single wire used in an electronic apparatusaccording to another exemplary embodiment of the present invention; and

FIG. 4 is a data format of the signals shown in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Exemplary embodiments of the present invention will now be described indetail with reference to the accompanying drawings.

FIG. 1 is a view illustrating the configuration of an electronicapparatus according to an exemplary embodiment of the invention.

Referring to FIG. 1, an electronic apparatus 100 according to thisembodiment may include a main electronic apparatus 110 and asub-electronic apparatus 120.

A single wire C is electrically connected between the main electronicapparatus 110 and the sub-electronic apparatus 120.

The main electronic apparatus 110 may include a control unit 111 and aswitching unit 112.

The control unit 111 may receive a detection signal from thesub-electronic apparatus 120 and transmit a response signal to thesub-electronic apparatus 120. Since the transmission and reception ofthese signals between the main electronic apparatus 110 and thesub-electronic apparatus 120 is performed using the single wire C, asignal transmission path therein needs to be switched.

The switching unit 112 switches the signal transmission path therein totransmit and receive the above-described signals.

The switching unit 112 may include first through third switches SW1 toSW3, a detection resistor R1 and pull-up resistors R1 and R2.

The first switch SW1 is opened when the detection signal from thesub-electronic apparatus 120 is transmitted to the control unit 111.When the response signal from the control unit 111 is transmitted to thesub-electronic apparatus 120, the first switch SW1 is closed accordingto a switching signal S1 from the control unit 111.

The second switch SW2 is closed in order to transmit the detectionsignal from the sub-electronic apparatus 120 to the control unit 111, sothat power from the detection resistor R1, connected to an operatingpower Vcc terminal, can be transmitted to the sub-electronic apparatus120.

The third switch SW3 and the pull-up resistor R2 may be additionallyconnected in parallel with the second switch SW2 and the detectionresistor R1, respectively, to thereby supply power having a differentvoltage level to the sub-electronic apparatus 120. That is, theoperating powers of the sub-electronic apparatus 120 and the mainelectronic apparatus 110 can have different voltage levels from eachother.

The above-described signals and powers are transmitted between thesub-electronic apparatus 120 and the main electronic apparatus 110through the single wire C.

The sub-electronic apparatus 120 may include a detection unit 121 and anoperation unit 122.

The detection unit 121 may include a variable resistor or a thermister.Further, the detection unit 121 may be supplied with power from the mainelectronic apparatus 110, detect status information inside thesub-electronic apparatus 120 and transmit a detection signal having thedetected status information to the main electronic apparatus 110.

The operation unit 122 may receive the response signal from the mainelectronic apparatus 110 and perform a predetermined operation.Specifically, the operation unit 122 may perform the main operation ofthe sub-electronic apparatus 120 or detect voltage, current ortemperature levels or various kinds of physical quantities and transmitthe detected results to the main electronic apparatus 110.

The signal transmission and reception between the main electronicapparatus 110 and the sub-electronic apparatus 120 will be describedwith reference to the drawings.

FIG. 2 is a view illustrating the structures of signals beingtransmitted and received through a signal wire used in an electronicapparatus according to an exemplary embodiment of the invention.

Referring to FIGS. 1 and 2, since the main electronic apparatus 110 andthe sub-electronic apparatus 120 are connected to each other using thesingle wire C, the structures of signals being transmitted and receivedneed to be set to satisfy the single wire C.

First, when the main electronic apparatus 110 and the sub-electronicapparatus 120 are connected to each other using the single wire C, thecontrol unit 111 of the main electronic apparatus 110 controls theon/off operation of each of the first and second switches SW1 and SW2 ofthe switching unit 112. That is, the control unit 11 opens the firstswitch SW1 and closes the second switch SW2 so that the operating powerVcc is transmitted to the detection resistor R1 and the detection unit121.

A voltage level V_(AN) of the status information detected by thedetection unit 121 is determined by the following equation: operatingpower Vcc*(resistance of detection unit 121)/(resistance of detectionunit 121+resistance of the detection resistor R1). Therefore, thevoltage level of the detection signal can be set to be different fromthat of the response signal.

Then, the detection signal having the status information is transmittedto the control unit 111 of the main electronic apparatus 110 from thesub-electronic apparatus 120 through the single wire C.

The control unit 111 of the main electronic apparatus 110 then closesthe first switch SW1 and opens the second switch SW2 so that theresponse signal from the control unit 111 is transmitted to theoperation unit 122 of the sub-electronic apparatus 120. The responsesignal may be a Pulse Width Modulation (PWM) control signal from thecontrol unit 111 to control the operation of the operation unit 122 ofthe sub-electronic apparatus 120.

In FIG. 2, the waveform of the detection signal and the control signalbeing transmitted and received as described above is shown.

That is, the detection signal and the control signal are shown to havedifferent signal widths T_(AN) and T_(DA) and different voltage levelsV_(AN) and Vcc, such that the detection signal and the response signalhaving different formats are transmitted and received through the singlewire C.

FIG. 3 is a view illustrating the structures of signals beingtransmitted and received through a single wire used in an electronicapparatus according to an exemplary embodiment of the invention.

Referring to FIGS. 1 and 3, like the structures of the signals beingtransmitted and received, the main electronic apparatus 110 and thesub-electronic apparatus 120 are connected to each other through thesingle wire C, the structures of the signals being transmitted andreceived needs to be set suited for the single wire C.

The control unit 111 controls the on/off operation of the first andsecond switches SW1 and SW2 of the switching unit 112. That is, thecontrol unit 111 opens the first switch SW1 and closes the second switchSW2 so that the operating power Vcc is transmitted to the detectionresistor R1 and the detection unit 121, and the detection signal havingthe status information is transmitted from the sub-electronic apparatus120 to the control unit 111 of the main electronic apparatus 110 throughthe single wire C (see reference character A in FIG. 3).

Then, the control unit 111 of the main electronic apparatus 110 closesthe first switch SW1 and opens the second switch SW2 so that the controlunit 111 and the operation unit 122 can perform communication (seereference characters B through F in FIG. 3). Here, this communication isperformed using a time-division method.

Specifically, the control unit 111 releases a port transmitting a signal(see reference character B in FIG. 3) and then transmits a start signalindicating the start of signal transmission. Here, the start signal mayhave a low voltage level (see reference character C in FIG. 3). Thecontrol unit 111 releases the port again (see reference character D inFIG. 3). The operation unit 122 transmits to the control unit, anacknowledge signal indicating the start signal has been received (seereference character E in FIG. 3). Then, the operation unit 122 releasesthe port to thereby perform data transmission and reception between thecontrol unit 111 and operation unit 122 (see reference character F inFIG. 3).

Here, when a signal is set for time division, a time Ts of the startsignal is set to be greater than a time Tack of the response signal. Asfor the time Ts of the start signal, an address is determined accordingto timing to thereby perform a predetermined operation.

FIG. 4 is view illustrating a data format of the signals shown in FIG.3. As shown in FIG. 4, the data format of the signals being transmittedor received between the main electronic apparatus 110 and thesub-electronic apparatus 120 may consist of analog, including the statusinformation of the detection signal being transmitted from thesub-electronic apparatus 120 to the main electronic apparatus 110, startand address indicating that a signal starts to be transmitted from themain electronic apparatus 110 and indicating a data type of the signal,data containing data of the signal, and end indicating the transmissionof the signal is terminated. The status information contained in theanalog may be analog data detected by the detection unit 121 of thesub-electronic apparatus 120. The start and address, the data and theend may be digital data by the control unit 111 of the main electronicapparatus 110 or the operation unit 122 of the sub-electronic apparatus120. That is, the data format of the signal being transmitted andreceived through the single wire C may be a combination of an analogsignal and a digital signal.

The start and address may be variously set according to time division asshown in the following table.

TABLE TIME (ms) SIGNAL MIN AVG MAX T_(AN) TRANSMIT DETECTION SIGNAL — 57 T_(S) START 80 500 T_(S)(M1) FIRST ADDRESS OF START AND 80 100 120MEMORY T_(S)(M2) SECOND ADDRESS OF START AND 180 200 220 MEMORYT_(S)(M3) THIRD ADDRESS OF START AND 280 300 320 MEMORY T_(ack)ACKNOWLEDGE 10 30 50

Referring to Table, and FIGS. 3 and 4, time assigned to the start signalthat is contained in the start and address is set to 100 msec, 200 msecor 300 msec on average. When a plurality of sub-electronic apparatusesare connected to a main electronic apparatus, correspondingsub-electronic apparatuses among the plurality of sub-electronicapparatuses may be controlled or a diverse array of controlling may beset to one sub-electronic apparatus. For example, as described above,when the operation unit 122 can detect voltage, current, temperature orvarious kinds of physical quantities, the control unit 111 may ask theoperation unit 122 to transmit various types of detection data accordingto the above-described addresses. Furthermore, in order that a detectionsignal, a start signal and an acknowledgement signal having differentsignal formats are transmitted and received through a single wire, timesthereof may be set to be different from each other.

As described above, according to embodiments of the invention, anelectronic apparatus, for example, a fuel cell circuit or a printer,which requires a cartridge, a main electronic apparatus performing themain operation and a sub-electronic apparatus forming a cartridge andaccompanying circuitry are connected through a single wire, statusinformation about a fuel cell cartridge or an ink cartridge istransmitted, and control and communication are performed using thesingle wire, thereby reducing physical device dimensions andmanufacturing costs.

As set forth above, according to exemplary embodiments of the invention,as a main electronic apparatus and a sub-electronic apparatus areconnected through a single wire, status information can be transmittedand control and communication can be performed through the single wire,thereby reducing physical device dimensions and manufacturing costs.

While the present invention has been shown and described in connectionwith the exemplary embodiments, it will be apparent to those skilled inthe art that modifications and variations can be made without departingfrom the spirit and scope of the invention as defined by the appendedclaims.

1. An electronic apparatus transmitting and receiving a signal through asingle wire, the electronic apparatus comprising: a sub-electronicapparatus transmitting a detection signal containing status informationthrough a single wire, and performing a predetermined operation uponreceiving a response signal to the detection signal; and a mainelectronic apparatus receiving the detection signal through the singlewire and transmitting the response signal having a different signalformat from the detection signal to the sub-electronic apparatus.
 2. Theelectronic apparatus of claim 1, wherein the main electronic apparatuscomprises: a control unit transmitting the response signal according tothe status information upon receiving the detection signal; and aswitching unit switching a transmission path therein according to thereception of the detection signal and the transmission of the responsesignal.
 3. The electronic apparatus of claim 2, wherein thesub-electronic apparatus comprises: a detection unit detecting internalstatus of the sub-electronic apparatus; and an operation unit performinga predetermined operation according to the response signal.
 4. Theelectronic apparatus of claim 3, wherein the switching unit comprises: afirst switch being opened when the detection signal is received andbeing closed when the response signal is transmitted to form atransmission path for the response signal; a detection resistor suppliedwith a predetermined operating power and electrically connected with thedetection unit of the sub-electronic apparatus to detect internal statusof the sub-electronic apparatus; and a second switch being closed beforethe detection signal is received to electrically connect the detectionresistor and the detection unit, and being opened when the responsesignal is transmitted.
 5. The electronic apparatus of claim 4, whereinthe switching unit further comprises: a pull-up resistor connected inparallel with the detection resistor, receiving the operating power andtransmitting the operating power to the operation unit; and a thirdswitch forming a transmission path for the operating power beingtransmitted to the operation unit from the pull-up resistor.
 6. Theelectronic apparatus of claim 3, wherein the control unit transmits aPulse Width Modulation (PWM) control signal in order to control theoperation unit according to the detection signal.
 7. The electronicapparatus of claim 3, wherein the control unit transmits a start signalaccording to time division to indicate transmission of a signal, theoperation unit transmits an acknowledgement signal according to timedivision to indicate acknowledgement of reception of the start signal,and a communication signal containing data information according to timedivision is transmitted and received between the operation unit and thecontrol unit.
 8. The electronic apparatus of claim 7, wherein a dataformat of a signal being transmitted and received between thesub-electronic apparatus and the main electronic apparatus through thesingle wire comprises: analog containing status information of thedetection signal; start and address indicating transmission of thesignal from the main electronic apparatus and indicating a data type ofthe signal; data containing data of the signal; and end indicatingtermination of the transmission of the signal.